Multiple louver  damper



March -3, 1964 v R. H. BISHOP 3,123,098

MULTIPLE LOUVER DAMPER Filed Aug. 17, 1961 2 Sheets-Sheet 1 FIG! INVENTOR. ROBERT H. BISHOP March 3, 1964 R. H. BISHOP 3,123,098

MULTIPLE LOUVER DAMPER Filed Aug. 17, 1961 2 Sheets-Sheet 2 z 3 H53 35 F|G.2

INV EN TOR.

ROBERT H. BISHOP BY A TTORNEYS United States Patent. 0

v 3,123,698 MULTIPLE LGUVER DAMPER RobettI-l; Bishop, 8983i. ParkSh', Champaign', Iii. Filed Aug. 17, 1961, Ser; No. 132,123

3 Claims. (Cl. 137601) The present invention relates to a multiple louver damper of the type wherein a substantially airtight structure is achieved when the louver blades of the damper are in closed position;

The particular object of the present invention is to provide a multiplewlouver damper having sealing m'ea'ns, uniquely arranged in such a manner so as to achieve a substantially airtight seal not only between adjacent louver blades, but'b'etween such blades and 'a-blade supporting damper frame.

Anotherobject of the present invention resides in the provision of'a multiple louver damper having damper blade'sof 'such a design that when in closed position they may be seated tightly against a sealing means carried by the damper frame, but may move away from the sealing eanswhile opening and thus prevents binding;

A further object of the present invention is to provide a multiple louver-damper having means whereby damper sealing means may be adjusted with respect to the damper frame to insure a uniform seal between damper blades and frame.

A still further object of the present invention is to provide a damper structure having no metal-tometal contact between damper components, thus curtailing objectionable vibration and noise.

To accomplish the foregoing objectives there is contemplated a multiple louver damper comprising a rec tangular frame and a plurality of louver blades pivotally mounted in the frame for vertical swinging motion with respect thereto. The individual louver blades are sup.- ported upona shaft or shaft sections which extend outwardly from the blade ends and have projectingends adapted to be received within seali'ri'g sleeve bearings disposed in openings provided in' theside members of the frame. Two types of-louverblades are provided for the damper of the present invention, there being'one lower blade and one or more upper blades. Each of the blades are providedwith co actingsealing elements in orderto afford a completely air tight-seal between adjacent blades in closed position. The top and bottom andside members of the damer frame are formed from aluminum extrusions oflike design. Each member is provided with a laterally opening channel recess, adapted to retain a resilient sealing means. This frame carried sealing means acts to form a substantially continuous seal between the frame and the blades in closed position along a line adjacent to the marginal edges of a generally plane surface formed by the rear surfaces of'the blades. To complement the seal formed between adjacent blades, between the blades and the supporting frame, and between thesupporting frame and the several blade supporting shafts, theframe members are provided with an outward- 1y opening recess adapted to-receive a sealing means in order to permit sealing of the frame with respect to'a fr'ameenclosin'g unit casing, duct or Wall opening.-

Ina second embodiment of the present invention a specially designed sealing clip is provided to adjustably atlix frame carried sealing means to insure uniform engagement of such sealing means against the louver blades.

In describing the invention reference may be made to the accompanying drawings wherein;

FIGURE 1 is a partially sectioned perspective view of a multiple louver damper constructed in accordance with the present invention;

FIGURE'Z is a sectional view taken along, lines 2-2 of FIGURE 1 showing the louver blade operating and supporting means in position;

FIGURE 3 is a View similar to view 2, but showing the louver blades in open position;

FIGURE 4 is afragmentary sectional View taken along lines 4- 4 of FIGURE 2;

FIGURE 5 is a fragmentary sectional view of the hinge portion ofthe'upper louver blade shown in FIGURES 2 and 3; and

FIGURE 6 is a fragmentary sectional view similar to FEGURE 4, but showing the secondembodiment'ofthe present invention.

As shown, the multiple louver damper ofth'e-present invention is generally indicated by l and may be positioned Within a-unit casing, duct or Wall openingl; The damper broadly comprises a'rectangularframe having like top and bottom frame members 3 and 3 and Vertically disposed like side frame members 4 andi. The top and bottom and side frame members may be' joined in any suitable manner as by welding and maybe-formed of any suitable material such as heavy aluminum extrusions.

Upper and lower blades 5' and'eare formed with smooth, fiat rearwardly facing surfaces and are rolled over along their upper marginal edges to form generally cylindrical, offset hinge portions 7 and 8 respectively; Theforwardly facing surfaces of blades 5 anddm'ay be of any desired design, adapted to enhance the structural stability of the'blades. Louver blades 5 and e are supported for vertical swinging motion about their upper edges and within the damper structure by means of shaft sections d and 16 adapted to be received within the hinged portions 7 and s'respectively'. Shaft sections 2 and in a like manner, shaft sections it), are adapted to be supported with respect to the damper frame structure by being received within bearing seal sleeve members lit, fitted within properly positioned holes 12-provided inthe side frame members 4 and 4. Bearing -member 11 may be formed of any'suitable material-such as nylon in order to effect a seal between supportingshaft sections 9 "and ltl'and frame members 4 and- 4';

Louver blades 5 and 6 may be swungto openor closed positions by means of any suitably actuated operating means comprising an operating rodlinkage 13 and brashets 14 and 15, which may be atlixed in any suitable manner to louver blades 5 and 6: Reciprocating rod-13 may be passed through any suitable opening in the bottom of the duct 2, not shown, and is pivotally'connected to brackets 14 and 15 at points 1-6 and 1'7.

If desired, supporting shaft sections 9, and in a like manner, supporting shaft sections it may each be formed as a-single shaft and be rigidly'atfixed to the blade hinged portions, rather than being formed as two parts, as shown in'PIGURE 4. In this construction, pivotal motion of thelouver blades is'eifected by-rotation of the several supporting shafts; any suitable means being provided to effect synchronized rotation'of'the shafts. It is obvious that in this form of the invention suitable openi'ngs would-be provided in the side wallsof the duct 2 to permit passage of outwardly extending portionsof the respective shafts. I

Referring-now to FIGURE 5 it will be seen that hinge portion 7, in an area generally designated by 18,- is reduced in thickness by the deletion of material from its outwardly facing surface. Area 13' comprises both a curved section of hinge portion 7 and the immediately adjacent plane surface portion thereof, which adjoins the rear plane surface portion of louver blade 5" and is disposed at an angle thereto. In a like manner respective portions of hinge portion 8 of louver blade 6 are reduced in thickness in an area generally designated as 19. A

longitudinally extending, outwardly projecting pointed contact bearing surface 2% is disposed on the curved surface of hinge portion 7 adjacent area 18. A like pointed contact bearing surface 21 is provided on hinge portion 3. The purpose of this specific hinge construction will be hereinafter described.

The free swinging marginal edge of louver blade is bent laterally to form a flange member generally designated as 22, the outwardly extending portion of which is formed into a channel recess 23 adapted to retain a resilient sealing means 2.4 of any suitable material, such as sponge rubber. From FIGURES 1 and 2 it will be apparent that an effective seal is achieved between adjacent louver blades 5 and 6 in closed position, by the sealing contact formed by co-acting sealing elements in the form of pointed bearing surface 21 and the resilient sealing means 24.

The free swinging marginal edge of louver blade 6 is laterally bent to form a flange 25. A laterally projecting ridge 26 is disposed at the apex formed by the plane surface of blade 6 and flange 25. The purpose of this lower louver blade structure will be hereinafter described.

The inwardly extending flange portions of top and bottom frame members 3 and 3 are provided with laterally opening channel recesses 27 and 23 which are adapted, respectively, to retain resilient sealing means 29 and 36 which may be formed of any suitable material, such as sponge rubber. In a like manner, the inwardly extending flange portions of side frame members 4 and 4 are in a like manner provided with laterally opening channel recesses 31 and 32 (not shown), adapted to retain resilient sealing means 33 and 34, respectively.

Reference now being made to FIGURES 2 and 4 it will be apparent that the novel structure of the present invention permits an effective seal between not only adjacent louver blades in closed position but between marginal portions of a generally plane surface formed by the smooth, flat rearwardly facing portions of such blades and the resilient sealing means carried on supporting frame members 3, 3', 4 and 4. It will be particularly noted that when the blades are in closed position sealing means 29 acts to effect a seal against hinge portion 7 of blade 5 and sealing means 3% acts to eifect a seal aginst ridge 26- carried on blade 6.

By reference now to FIGURES 2 and 3, showing louver blade 5 in closed and open position, it will be seen that the provision of the reduced hinge thickness in area 18 of hinge portion 7 permits blade 5 to move away from the seal 29, as it opens and thus prevents binding. It will be also noted that the reduced hinge thickness portions in areas 13 and '19 of hinge portions 7 and 8 will permit blades 5 and 6 to move away from sealing means 33 and 34 as they open and thus prevent binding.

To complement the seals formed between adjacent blades and between the louver supporting frame and the respective blades, provision is made for a seal between the frame members and the duct 2. in which they are disposed. ln understanding this latter sealing provision, reference may be made to FIGURES 2 and 4, wherein it will be seen that top and bottom frame members 3 and 3' and side frame members 4 and 4 are provided with outwardly opening channel recesses 35, 36, 39 and 44 which are adapted respectively to receive leg shaped sealing means 37, 38, 41 and 42.

A second embodiment of the present damper construction may be seen by reference to FlGURE 6. In this embodiment, side damper frame member 43 is a modification of member 4, wherein the laterally opening sealing means retaining recess 32 of member 4' is dispensed with and a specially designed clip 44 is adapted to adjustably retain sealing means 34 in position with respect to member 43. Clip 44 comprises a stepped bracket having parallel legs 45 and 46 and an intermediately disposed leg connecting flange 47. Clip 44 is adapted to be adjustably affixed with respect to member 43 by any suitable means such as a lock bolt 49 which is adapted to pass through slot opening 48, provided in leg 46, and a suitable hole 5%, provided in member 43, and be locked in position by spring clip 51. Clip 45 is additionally provided wih a pointed projection 52, formed integrally with leg 45, which acts in conjunction with an oppositely disposed pointed projection 53, formed integrally with member 43, to grip sealing means 34 when clip 44 is afiixed to member 43. Member 43, like member 4', is also provided with an outwardly opening recess 49 adapted to retain a sealing means 42, and holes 12 adapted to receive bearing seal sleeve members 11.

By viewing FIGURE 6, it will be seen that sealing means 34 may be adjustably placed in uniform engagement with the rearwardly facing smooth flat surface formed by the several louver blades in closed position and then be held in this position relative to the frame member 43 by means of clip 44. While not shown, it is apparent that all of the frame members may be formed in a manner similar to member 43 and that clip members similar to clip 44 may be used to retain the respective sealing means 29, 30, 33 and 34 in position. Also, it will be appreciated that an individual clip member '44 may be formed of single piece construction and be adapted to extend along the full length of any one frame member, or that a plurality of clips having a shorter length, but formed with the same cross-sectional design as clip 44, may be used to retain sealing means 34 with respect to member 43 at several spaced apart points. Additionally, pointed projections 52 and 53 may extend along the full lengths of member 43 and clip 44 or be interrupted at spaced apart points.

While only showing and describing an upper louver blade 5 and a lower blade 6, I do not intend to be limited to the number of blades which may be employed in a particular damper installation, it being apparent that three or more 'blade damper structures are possible, by merely adding an appropriate number of blades, similar in design to upper blade 5. In such a multiblade construction, pointed contact bearing surface 20, of any intermediately disposed blade 5 would be adapted to effect a seal with the cooperating sealing means 24 of an adjacent upper blade and sealing means 24 of such intermediately disposed blade would be adapted to effect a seal with the pointed contact bearing surface 20 or 2d of an adjacent lower blade, as the case might be.

In constructing a multiple louver damper after the present invention a substantially complete air tight structure is achieved. Additionally, in the damper of the present invention there is no metal-to-metal contact between damper parts, thus, curtailing objectionable vibration and noise. Also, by forming the damper structural components from extruded aluminum, a non-corrosive and lightweight, but structurally sturdy design, assuring a more positive seal between damper components, is obtained. Further, reference is made to the adjustable sealing means retaining clip of the present invention whereby the sealing means carried by the frame may be quickly and accurately placed with respect to the louver blades.

Special reference is made to the fact that the louver .blades of the present damper construction are each pivoted about one marginal edge thereof, rather than about the midpoint of the blades, as with some dampers, and are provided with smooth flat rearwardly facing surfaces. This constmction permits the ends of each blade to close tightly against the frame seal. Also, such design permits a more accurate modulation of air passing through the damper in blade open position.

It will be appreciated that the terms, upper, lower and side, as used to describe damper components, are merely employed to indicate the relative placement of such components with respect to one another, and accordingly I do not wish to be limited thereby, it being apparent that a damper constructed in accordance with the present invention might be installed in an inverted, horizontal, or any other desired position.

I claim:

1. A multiple louver damper comprising a frame and a plurality of louver blades disposed therein, said blades including a lower blade and at least one upper blade, each of said blades being provided with a hinge portion extending along the upper marginal edge thereof for pivotally mounting said blade for vertical swinging motion with respect to said frame, an outwardly projecting pointed contact bearing surface formed integrally with and extending longitud'nally of said hinge portion of each of said blades, 21 laterally projecting ridge formed adjacent to the free swinging marginal edge of said lower blade, the free swinging marginal edge of said upper blade being provided with a laterally offset channel recess adapted to receive a resilient sealing means, said sealing means of said blade channel recess, while in blade closed position, being adapted to overlap the hinge portion of an adjacent lower blade and seal against the pointed contact bearing surface tnereof, said frame comprising top and bottom members and side members, each of said frame members having a laterally opening channel recess, a first sealing means received within and projecting from each of said laterally opening frame channel recesses, such that when said blades are in closed position, said first sealing means carried by said frame members is adapted to seal against the plane vertically extending marginal edges of said blades, said first sealing means carried by said top frame member being adapted to seal against the hinge portion of the uppermost blade of said blades, and said first sealing means carried by said bottom frame member being adapted to seal against said ridge formed on said lower blade, and each of said frame members being formed with an outwardly opening recess adapted to receive a second sealing means adapted to effect sealing engagement between said frame members and the Walls of an opening in a structure within which said frame is mounted, said hinge portion of each of said blades being formed by rolling over the upper marginal edge thereof to form a generally cylindrical cavity, laterally offset from a generally plane portion of said blade, and said blades being provided with supporting shafts which are disposed within said cylindrical cavities and adapted to extend axially outwardly on either end thereof to be received within bearing sleeve seal members disposed in openings provided in said side frame members, said hinge portions of said blades being reduced in thickness between said outwardly projecting pointed contact hearing surface and said generally plane portion of said blades, thereby permitting said uppermost blade to swing away from said sealing means carried by said top frame memher, and said lower blades to swirl away from said sealing means carried by said side frame members as said blades open to thus prevent binding.

2. A multiple louver damper according to claim 1, wherein each of said blades is provided with a rearwardly extending bracket rigidly affixed thereto, and each of said brackets is pivotally affixed at its outwardly projecting end to a reciprocating, blade actuating rod.

3. A multiple louver damper according to claim 1, in which said supporting shafts are aflixed to the hinge portions of said blades for rotation therewith, and means are provided to effect rotation of said shafts to operate said blades.

References Cited in the file of this patent UNITED STATES PATENTS 

1. A MULTIPLE LOUVER DAMPER COMPRISING A FRAME AND A PLURALITY OF LOUVER BLADES DISPOSED THEREIN, SAID BLADES INCLUDING A LOWER BLADE AND AT LEAST ONE UPPER BLADE, EACH OF SAID BLADES BEING PROVIDED WITH A HINGE PORTION EXTENDING ALONG THE UPPER MARGINAL EDGE THEREOF FOR PIVOTALLY MOUNTING SAID BLADE FOR VERTICAL SWINGING MOTION WITH RESPECT TO SAID FRAME, AN OUTWARDLY PROJECTING POINTED CONTACT BEARING SURFACE FORMED INTEGRALLY WITH AND EXTENDING LONGITUDINALLY OF SAID HINGE PORTION OF EACH OF SAID BLADES, A LATERALLY PROJECTING RIDGE FORMED ADJACENT TO THE FREE SWINGING MARGINAL EDGE OF SAID LOWER BLADE, THE FREE SWINGING MARGINAL EDGE OF SAID UPPER BLADE BEING PROVIDED WITH A LATERALLY OFFSET CHANNEL RECESS ADAPTED TO RECEIVE A RESILIENT SEALING MEANS, SAID SEALING MEANS OF SAID BLADE CHANNEL RECESS, WHILE IN BLADE CLOSED POSITION, BEING ADAPTED TO OVERLAP THE HINGE PORTION OF AN ADJACENT LOWER BLADE AND SEAL AGAINST THE POINTED CONTACT BEARING SURFACE THEREOF, SAID FRAME COMPRISING TOP AND BOTTOM MEMBERS AND SIDE MEMBERS, EACH OF SAID FRAME MEMBERS HAVING A LATERALLY OPENING CHANNEL RECESS, A FIRST SEALING MEANS RECEIVED WITHIN AND PROJECTING FROM EACH OF SAID LATERALLY OPENING FRAME CHANNEL RECESSES, SUCH THAT WHEN SAID BLADES ARE IN CLOSED POSITION, SAID FIRST SEALING MEANS CARRIED BY SAID FRAME MEMBERS IS ADAPTED TO SEAL AGAINST THE PLANE VERTICALLY EXTENDING MARGINAL EDGES OF SAID BLADES, SAID FIRST SEALING MEANS CARRIED BY SAID TOP FRAME MEMBER BEING ADAPTED TO SEAL AGAINST THE HINGE PORTION OF THE UPPERMOST BLADE OF SAID BLADES, AND SAID FIRST SEALING MEANS CARRIED BY SAID BOTTOM FRAME MEMBER BEING ADAPTED TO SEAL AGAINST SAID RIDGE FORMED ON SAID LOWER BLADE, AND EACH OF SAID FRAME MEMBERS BEING FORMED WITH AN OUTWARDLY OPENING RECESS ADAPTED TO RECEIVE A SECOND SEALING MEANS ADAPTED TO EFFECT SEALING ENGAGEMENT BETWEEN SAID FRAME MEMBERS AND THE WALLS OF AN OPENING IN A STRUCTURE WITHIN WHICH SAID FRAME IS MOUNTED, SAID HINGE PORTION OF EACH OF SAID BLADES BEING FORMED BY ROLLING OVER THE UPPER MARGINAL EDGE THEREOF TO FORM A GENERALLY CYLINDRICAL CAVITY, LATERALLY OFFSET FROM A GENERALLY PLANE PORTION OF SAID BLADE, AND SAID BLADES BEING PROVIDED WITH SUPPORTING SHAFTS WHICH ARE DISPOSED WITHIN SAID CYLINDRICAL CAVITIES AND ADAPTED TO EXTEND AXIALLY OUTWARDLY ON EITHER END THEREOF TO BE RECEIVED WITHIN BEARING SLEEVE SEAL MEMBERS DISPOSED IN OPENINGS PROVIDED IN SAID SIDE FRAME MEMBERS, SAID HINGE PORTIONS OF SAID BLADES BEING REDUCED IN THICKNESS BETWEEN SAID OUTWARDLY PROJECTING POINTED CONTACT BEARING SURFACE AND SAID GENERALLY PLANE PORTION OF SAID BLADES, THEREBY PERMITTING SAID UPPERMOST BLADE TO SWING AWAY FROM SAID SEALING MEANS CARRIED BY SAID TOP FRAME MEMBER, AND SAID LOWER BLADES TO SWING AWAY FROM SAID SEALING MEANS CARRIED BY SAID SIDE FRAME MEMBERS AS SAID BLADES OPEN TO THUS PREVENT BINDING. 